DOCSLIB.ORG

Manual on Hydrometry

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Manual on Hydrometry Annexure I Table of Contents 1 INTRODUCTION 1 1.1 GENERAL 1 1.2 DEFINITION OF VARIABLES AND UNITS 2 2 PHYSICS OF RIVER FLOW 5 2.1 GENERAL 5 2.2 CLASSIFICATION OF FLOWS 5 2.3 VELOCITY PROFILES 8 2.4 HYDRAULIC RESISTANCE 10 2.5 UNSTEADY FLOW 14 2.6 BACKWATER CURVES 17 3 HYDROMETRIC NETWORK DESIGN 21 3.1 INTRODUCTION 21 3.2 NETWORK DESIGN CONSIDERATIONS 22 3.2.1 CLASSIFICATION 22 3.2.2 MINIMUM NETWORKS 22 3.2.3 NETWORKS FOR LARGE RIVER BASINS 23 3.2.4 NETWORKS FOR SMALL RIVER BASINS 23 3.2.5 NETWORKS FOR DELTAS AND COASTAL FLOODPLAINS 23 3.2.6 REPRESENTATIVE BASINS 24 3.2.7 SUSTAINABILITY 24 3.2.8 DUPLICATION AVOIDANCE 24 3.2.9 PERIODIC RE-EVALUATION 24 3.3 NETWORK DENSITY 24 3.3.1 WMO RECOMMENDATIONS 24 3.3.2 PRIORITISATION SYSTEM 25 3.3.3 STATISTICAL AND MATHEMATICAL OPTIMISATION 26 3.4 THE NETWORK DESIGN PROCESS 26 4 SITE SELECTION OF WATER LEVEL AND STREAMFLOW STATIONS 28 4.1 DEFINITION OF OBJECTIVES 28 4.2 DEFINITION OF CONTROLS 28 4.3 SITE SURVEYS 29 4.4 SELECTION OF WATER LEVEL GAUGING SITES 31 4.5 SELECTION OF STREAMFLOW MEASUREMENT SITE 31 5 MEASURING FREQUENCY 34 5.1 GENERAL 34 5.2 STAGE MEASUREMENT FREQUENCY 35 5.3 CURRENT METER MEASUREMENT FREQUENCY 36 6 MEASURING TECHNIQUES 38 6.1 STAGE MEASUREMENT 38 6.1.1 GENERAL 38 6.1.2 VERTICAL STAFF GAUGES 39 6.1.3 INCLINED STAFF OR RAMP GAUGES 42 6.1.4 CREST STAGE GAUGES 43 6.1.5 ELECTRIC TAPE GAUGES 44 6.1.6 FLOAT SYSTEM WITH AUTOGRAPHIC RECORDING 45 6.1.7 FLOAT SYSTEM WITH DIGITAL RECORDING 50 6.1.8 PRESSURE SENSORS (TRANSDUCERS) 52 6.1.9 DATA LOGGERS 59 Hydrometry January 2003 Page i Design Manual – Hydrometry (SW) Volume 4 6.1.10 SELECTION OF STAGE AND WATER LEVEL SENSORS AND RECORDING EQUIPMENT 63 6.2 INTRODUCTION TO VELOCITY AREA METHOD OF STREAMFLOW MEASUREMENT 64 6.2.1 BASIC PRINCIPLES 64 6.2.2 FACTORS AFFECTING VELOCITY DISTRIBUTION IN OPEN CHANNELS 66 6.2.3 DISTRIBUTION OF VELOCITY 69 6.3 FLOAT MEASUREMENT 70 6.3.1 BACKGROUND 70 6.3.2 TYPES OF FLOAT 71 6.3.3 FLOAT MEASUREMENT TECHNIQUE 72 6.3.4 DETERMINATION OF DISCHARGE FROM SURFACE FLOAT VELOCITY MEASUREMENTS 74 6.4 CURRENT METER STREAMFLOW MEASUREMENT 76 6.4.1 INTRODUCTION 76 6.4.2 ROTATING ELEMENT CURRENT METERS 76 6.4.3 TYPES OF CURRENT METER 78 6.4.4 METHODS OF SUSPENSION AND DEPLOYMENT OF CURRENT METERS 81 6.4.5 SPACING OF VERTICALS 86 6.4.6 MEASUREMENT OF WIDTH, HORIZONTAL DISTANCE OR POSITION IN THE HORIZONTAL 88 6.4.7 MEASUREMENT OF DEPTH 91 6.4.8 SKEW EFFECTS 97 6.4.9 METHODS OF ESTIMATING MEAN VELOCITY IN THE VERTICAL 98 6.4.10 LEGITIMATE SHORT CUTS 100 6.4.11 COMPUTATION OF DISCHARGE 100 6.4.12 ERROR ANALYSIS VELOCITY AREA METHOD 101 6.4.13 MINIMISING ERRORS IN CURRENT METER DISCHARGE MEASUREMENTS 106 6.4.14 ELECTROMAGNETIC CURRENT METER 106 6.5 ACOUSTIC DOPPLER CURRENT PROFILER (ADCP) 107 6.5.1 INTRODUCTION 107 6.5.2 BASIC PRINCIPLES OF DOPPLER VELOCITY METERS 108 6.5.3 ADCP FUNCTIONING AND COMPONENTS 110 6.5.4 PRACTICAL USE OF THE ADCP 113 6.5.5 COLLECTING DISCHARGE DATA WITH A SONTEK ADP 118 6.5.6 PROCESSING OF SONTEK ADP DATA 120 6.5.7 ADCP - GLOSSARY OF TERMS 123 6.6 SLOPE - AREA METHOD 125 6.6.1 INTRODUCTION 125 6.6.2 PRINCIPLES OF THE METHOD OF MEASUREMENT 125 6.6.3 ESTIMATION OF VELOCITY HEAD AND DISCHARGE 128 6.6.4 ESTIMATION OF MANNING’S COEFFICIENT 128 6.6.5 COMPOSITE SECTIONS 129 6.6.6 STATE OF FLOW 130 6.7 COMPARISON AND APPLICATION OF DIFFERENT FLOW MEASUREMENT TECHNIQUES 130 7 EQUIPMENT SPECIFICATIONS 134 7.1 INTRODUCTION 134 7.2 PREPARATION OF STAGE AND STREAM FLOW MEASUREMENT INSTRUMENTATION AND EQUIPMENT TENDER SPECIFICATIONS 135 7.2.1 INTRODUCTION 135 7.2.2 SITE SURVEYS AND INSTALLATION PLANNING 135 7.2.3 TENDER PACKAGES 136 Hydrometry January 2003 Page ii Design Manual – Hydrometry (SW) Volume 4 7.2.4 RESOLUTION AND ACCURACY 137 7.2.5 HYDROMETRIC SENSOR AND EQUIPMENT SELECTION CRITERIA 137 7.2.6 INSTRUMENT AND EQUIPMENT SPECIFICATIONS 138 7.2.7 OTHER ITEMS TO BE INCLUDED IN THE SPECIFICATIONS 141 7.3 INTERPRETATION OF EQUIPMENT SPECIFICATION AND ASSESSMENT OF PRODUCTS AND SUPPLIERS 143 7.3.1 INTERPRETING EQUIPMENT SPECIFICATIONS 143 7.3.2 EVALUATION OF SPECIFICATIONS 143 7.4 EQUIPMENT SPECIFICATIONS 145 8 STATION DESIGN, CONSTRUCTION AND INSTALLATION 147 8.1 DESIGN AND INSTALLATION CRITERIA - WATER LEVEL MONITORING 147 8.1.1 STAFF GAUGES 147 8.1.2 BENCH MARKS 149 8.1.3 STILLING WELLS 149 8.1.4 DWLR - PRESSURE SENSOR TYPE 154 8.1.5 INSTRUMENT PROTECTION AND HOUSINGS 157 8.2 DESIGN AND INSTALLATION CRITERIA - CURRENT METER GAUGING INSTALLATIONS 158 8.2.1 GENERAL 158 8.2.2 WADING GAUGING SITES 159 8.2.3 BRIDGE GAUGING 159 8.2.4 CABLEWAY GAUGING 160 8.2.5 BOAT GAUGING 165 8.3 SITE OFFICES AND STORES 166 8.3.1 SITE TYPES 166 8.3.2 ASSUMPTIONS 167 8.3.3 GUIDELINES 167 8.3.4 POSSIBLE BUILDING REQUIREMENTS 168 9 REFERENCES 169 Hydrometry January 2003 Page iii Design Manual – Hydrometry (SW) Volume 4 1 INTRODUCTION 1.1 GENERAL The branch of Geophysics, which deals with the occurrence and movement of water in terms of quantities and quality on and below the surface of the earth except the oceans, in vapour, liquid or solid state, is termed Hydrology. For hydrological design and water resources assessment purposes proper estimates of river flow and river stages are required. Their measurement is the domain of hydrometry. Figure 1.1: Hydrometric station The measurement of river stages and discharges at the observation stations is dealt with in this Volume 4 “Hydrometry” of the “Manual on Hydrological Field Measurements and Data Processing”. This volume on hydrometry includes how measurements are made, with what equipment, where and when. Volume 4 consists of three parts: 1. Design Manual, in which the basic principles and procedures are put in context 2. Reference Manual, for details on specific topics, and 3. Field Manual, dealing with operational procedures at the observation station. This part of Volume 4 covers the Design Manual: ‘Hydrometry’. It is set up as follows: • Chapter 1 deals with definition of quantities and units and unit conversions. • Some basic hydraulic principles as far as relevant for hydrometry are dealt with in Chapter 2. • In Chapter 3 the design and optimisation of hydrometric networks are discussed. Network densities are related to measurement objectives, spatial variation of the phenomena and cost of installation and operation. Hydrometry January 2003 Page 1 Design Manual – Hydrometry (SW) Volume 4 • Once the network density has been specified the sites for the water levels and discharges have to be selected. Criteria for site selection are discussed in Chapter 4. • Next, in Chapter 5 the observation frequency to be applied for the various hydrological quantities in view of the measurement objectives and temporal variation of the observed processes are treated. • The measurement techniques for observation of hydrometric variables and related equipment are dealt with in Chapter 6. • Since the buyers of the hydrometric equipment are often neither sufficiently familiar with the exact functioning of (parts of) the equipment nor with the background of the specifications, remarks on the equipment specifications have been added in Chapter 7. The equipment specifications proper are covered in a separate and regularly updated volume: “Equipment Specification Surface Water”. • Guidelines on station design and equipment installation are dealt with in Chapter 8. In the Field Manual operational practices in running the network stations are given. It also includes field inspections, audits and last but not least, the topic of equipment maintenance and calibration. Notes • The content of this part of the manual deals only with hydrometric measurements in the States of Peninsular India. The equipment discussed is used or appropriate for use in the Hydrological Information System. Hence, the manual does not provide a complete review of all techniques and equipment applied elsewhere. • The procedures dealt with in this manual are conformably to BIS and ISO standards. It is essential that the procedures described in this manual are closely followed to guarantee a standardised approach in the entire operation of the Hydrological Information System. 1.2 DEFINITION OF VARIABLES AND UNITS In this section definitions, symbols and units of relevant quantities and parameters when dealing with hydrometry are given. The use of standard methods is an important objective in the operation of the Hydrological Information System (HIS). Standard methods require the use of a coherent system of units with which variables and parameters are quantified. This section deals with the system of units used for the measurement of hydrological quantities. Quantity Symbol Unit Quantity Symbol Unit Density Head -3 Density of water ρ kg.m Velocity head hv m -3 Density of sediment, ρs kg.m Pressure head hp m Relative density under water ∆=(ρs-ρ)/ρ [-] Energy head He m Pressure Slope Air pressure pa kPa Slope/gradient (general) S [-] Water pressure p kPa Bottom/bed slope/gradient S0 [-] Water surface slope/gradient Sw [-] Temperature Energy slope/gradient Se [-] o Water temperature T ,t C or K w w o Air temperature Ta ,ta C or K Discharge Flow velocity u, v, w m.s-1 Level, depth, area Discharge Q m3.s-1 2 -1 Water depth y, h m Discharge per unit width q m .s Wetted perimeter P m 2 Wetted area A m Characteristic numbers Hydraulic radius R m Reynolds number Re [-] Equilibrium or normal depth yn, hn m Froude number Fr [-] Critical depth yc, hc m Table 1.1: Overview of relevant quantities, symbols and units used in hydrometry Hydrometry January 2003 Page 2 Design Manual – Hydrometry (SW) Volume 4 General terms Control: The physical properties of a channel, natural or artificial, which determine the relationship between stage and discharge at a location in the channel.
Load more

Recommended publications
  • Manual on Hydrometry
    Government of India & Government of The Netherlands DHV CONSULTANTS & DELFT HYDRAULICS with HALCROW, TAHAL, CES, ORG & JPS VOLUME 4 HYDROMETRY DESIGN MANUAL Design Manual – Hydrometry (SW) Volume 4 Table of Contents 1 INTRODUCTION 1 1.1 GENERAL 1 1.2 DEFINITION OF VARIABLES AND UNITS 2 2 PHYSICS OF RIVER FLOW 5 2.1 GENERAL 5 2.2 CLASSIFICATION OF FLOWS 5 2.3 VELOCITY PROFILES 8 2.4 HYDRAULIC RESISTANCE 10 2.5 UNSTEADY FLOW 14 2.6 BACKWATER CURVES 17 3 HYDROMETRIC NETWORK DESIGN 21 3.1 INTRODUCTION 21 3.2 NETWORK DESIGN CONSIDERATIONS 22 3.2.1 CLASSIFICATION 22 3.2.2 MINIMUM NETWORKS 22 3.2.3 NETWORKS FOR LARGE RIVER BASINS 23 3.2.4 NETWORKS FOR SMALL RIVER BASINS 23 3.2.5 NETWORKS FOR DELTAS AND COASTAL FLOODPLAINS 23 3.2.6 REPRESENTATIVE BASINS 24 3.2.7 SUSTAINABILITY 24 3.2.8 DUPLICATION AVOIDANCE 24 3.2.9 PERIODIC RE-EVALUATION 24 3.3 NETWORK DENSITY 24 3.3.1 WMO RECOMMENDATIONS 24 3.3.2 PRIORITISATION SYSTEM 25 3.3.3 STATISTICAL AND MATHEMATICAL OPTIMISATION 26 3.4 THE NETWORK DESIGN PROCESS 26 4 SITE SELECTION OF WATER LEVEL AND STREAMFLOW STATIONS 28 4.1 DEFINITION OF OBJECTIVES 28 4.2 DEFINITION OF CONTROLS 28 4.3 SITE SURVEYS 29 4.4 SELECTION OF WATER LEVEL GAUGING SITES 31 4.5 SELECTION OF STREAMFLOW MEASUREMENT SITE 31 5 MEASURING FREQUENCY 34 5.1 GENERAL 34 5.2 STAGE MEASUREMENT FREQUENCY 35 5.3 CURRENT METER MEASUREMENT FREQUENCY 36 6 MEASURING TECHNIQUES 38 6.1 STAGE MEASUREMENT 38 6.1.1 GENERAL 38 6.1.2 VERTICAL STAFF GAUGES 39 6.1.3 INCLINED STAFF OR RAMP GAUGES 42 6.1.4 CREST STAGE GAUGES 43 6.1.5 ELECTRIC TAPE GAUGES 44
    [Show full text]
  • Hydrological Measurements
    Water Quality Monitoring - A Practical Guide to the Design and Implementation of Freshwater Quality Studies and Monitoring Programmes Edited by Jamie Bartram and Richard Ballance Published on behalf of United Nations Environment Programme and the World Health Organization © 1996 UNEP/WHO ISBN 0 419 22320 7 (Hbk) 0 419 21730 4 (Pbk) Chapter 12 - HYDROLOGICAL MEASUREMENTS This chapter was prepared by E. Kuusisto. Hydrological measurements are essential for the interpretation of water quality data and for water resource management. Variations in hydrological conditions have important effects on water quality. In rivers, such factors as the discharge (volume of water passing through a cross-section of the river in a unit of time), the velocity of flow, turbulence and depth will influence water quality. For example, the water in a stream that is in flood and experiencing extreme turbulence is likely to be of poorer quality than when the stream is flowing under quiescent conditions. This is clearly illustrated by the example of the hysteresis effect in river suspended sediments during storm events (see Figure 13.2). Discharge estimates are also essential when calculating pollutant fluxes, such as where rivers cross international boundaries or enter the sea. In lakes, the residence time (see section 2.1.1), depth and stratification are the main factors influencing water quality. A deep lake with a long residence time and a stratified water column is more likely to have anoxic conditions at the bottom than will a small lake with a short residence time and an unstratified water column. It is important that personnel engaged in hydrological or water quality measurements are familiar, in general terms, with the principles and techniques employed by each other.
    [Show full text]
  • Hydrological Standard for Water Quality Station Instrumentation
    HP 35 HYDROLOGICAL PROCEDURE HYDROLOGICAL STANDARD FOR HYDROLOGICAL PROCEDURE HP 35 WATER QUALITY STATION INSTRUMENTATION DEPARTMENT OF IRRIGATION AND DRAINAGE MALAYSIA DISCLAIMER The department or government shall have no liability or responsibility to the user or any other person or entity with respect to any liability, loss or damage caused or alleged to be caused, directly or indirectly, by the adaptation and use of the methods and recommendations of this publication, including but not limited to, any interruption of service, loss of business or anticipatory profits or consequential damages resulting from the use of this publication. Opinions expressed in DID publications are those of the authors and do not necessarily reflect those of DID. Copyright ©2018 by Department of Irrigation and Drainage (DID) Malaysia Kuala Lumpur, Malaysia. Perpustakaan Negara Malaysia Cataloguing-in-Publication Data HYDROLOGICAL STANDARD FOR WATER QUALITY STATION INSTRUMENTATION. HP 35 (HYDROLOGICAL PROCEDURE ; HP 35) ISBN 978-983-9304-40-4 1. Hydrological stations--Malaysia. 2. Hydrology--Malaysia. 3. Government publications--Malaysia. I. Department of Irrigation and Drainage Malaysia. II. Series. 551.5709595 All rights reserved. Text and maps in this publication are the copyright of the Department of Irrigation and Drainage Malaysia unless otherwise stated and may not be reproduced without permission. i PREFACE The Jabatan Pengairan dan Saliran Malaysia (JPS) uses continuous water-quality monitors to assess the quality of the surface water. A common monitoring-system in water-quality collection involves six parameters, which collects ammoniacal nitrogen, biochemical oxygen demand, chemical oxygen demand, dissolved oxygen, pH, and total suspended solids. The sensors that are used to measure water-quality parameters require field observation, cleaning, and calibration procedures, as well as thorough procedures in computing and publishing final records.
    [Show full text]
  • Water Quality Assessments - a Guide to Use of Biota, Sediments and Water in Environmental Monitoring - Second Edition
    Water Quality Assessments - A Guide to Use of Biota, Sediments and Water in Environmental Monitoring - Second Edition Edited by Deborah Chapman PUBLISHED ON BEHALF OF UNITED NATIONSEDUCATIONAL, SCIENTIFIC AND CULTURAL ORGANIZATION WORLD HEALTHORGANIZATION UNITED NATIONS ENVIRONMENT PROGRAMME Published by E&FN Spon, an imprint of Chapman & Hall, First edition 1992 Second edition 1996 © 1992, 1996 UNESCO/WHO/UNEP Printed in Great Britain at the University Press, Cambridge ISBN 0 419 21590 5 (HB) 0 419 21600 6 (PB) Apart from any fair dealing for the purposes of research or private study, or criticism or review, as permitted under the UK Copyright Designs and Patents Act, 1988, this publication may not be reproduced, stored or transmitted, in any form or by any means, without the prior permission in writing of the publishers, or in the case of reprographic reproduction only in accordance with the terms of the licences issued by the Copyright Licensing Agency in the UK, or in accordance with the terms of licenses issued by the appropriate Reproduction Rights Organization outside the UK. Enquiries concerning reproduction outside the terms stated here should be sent to the publishers at the London address printed on this page. The publisher makes no representation, express or implied, with regard to the accuracy of the information contained in this book and cannot accept any legal responsibility or liability for any errors or omissions that may be made. A catalogue record for this book is available from the British Library Ordering information Water Quality Assessments - A Guide to Use of Biota, Sediments and Water in Environmental Monitoring - Second Edition 1996, 651 pages published on behalf of WHO by F & FN Spon 11 New Fetter Lane London EC4) 4EE Telephone: +44 171 583 9855 Fax: +44 171 843 2298 Order on line: http://www.earthprint.com Table of Contents Foreword to the first edition Foreword to the second edition Summary and scope Acknowledgements Abbreviations used in text Chapter 1 - AN INTRODUCTION TO WATER QUALITY 1.1.
    [Show full text]
  • Scoping the Broad Scale Modelling Hydrology Programme
    Scoping the Broad Scale Modelling Hydrology Programme Stage 2 Strategic Programme R&D Technical Report FD2104 DEFRA / Environment Agency Flood and Coastal Defence R&D Programme Scoping the Broad Scale Modelling Hydrology Programme Stage 2 - Strategic Programme R&D Technical Report FD2104 Scoping the Broad Scale Modelling Hydrology Programme February 2002 Publishing Organisation DEFRA Flood Management Division Eastbury House 30-34 Albert Embankment London SE1 7TL Tel: 0207 270808 © Crown Copyright (DEFRA) February 2002 Copyright in the typographical arrangement and design rests with the Crown. This publication (excluding the logo) may be reproduced free of charge in any format or medium provided that it is reproduced accurately and not used in a misleading context. The material must be acknowledged as Crown copyright with the title and source of the publication specified. The views expressed in this document are not necessarily those of Defra or the Environment Agency. Its officers, servants or agents accept no liability whatsoever for any loss or damage arising from the interpretation or use of the information, or reliance on views contained herein. Dissemination status Internal: Released Internally External: Released to Public Domain Statement of Use Strategic planning of hydrological flood management R&D. Keywords Modelling, hydrology, river catchments, flood management, strategy and planning. Research contractors: Dr Ann Calver, Head of Hydrological Risks Division, CEH Wallingford (formerly the Institute of Hydrology), Maclean Building , Crowmarsh Gifford, Wallingford Oxon OX10 8BB, Tel: 01491 838800, Fax: 01491 692424 [email protected] Professor Howard S Wheater, Head of Environmental & Water Resource Engineering Department of Civil & Environmental Engineering, Imperial College, London SW7 2BU.
    [Show full text]
  • Environmental Protection Agency (EPA) Hydrometric Network Review
    Environmental Protection Agency (EPA) Hydrometric Network Review April 2016 JBA Project Manager Tom Sampson 24 Grove Island Corbally Limerick Ireland Revision History Revision Ref / Date Issued Amendments Issued to v1.0 / October 2015 Conor Quinlan, EPA V2.0 / December 2015 Updates following client review Conor Quinlan, EPA Final Report following client V3.0 / April 2016 Conor Quinlan, EPA review Update requested from ESB to V4.0 / August 2016 Conor Quinlan, EPA Table 5-2. Contract This report describes work commissioned by Matthew Craig, on behalf of the Environmental Protection Agency (EPA), by a contract agreement signed 06/08/2015. The EPA’s representative for the contract was Conor Quinlan. Maxine Zaidman, Barry Hankin and Tom Sampson of JBA Consulting carried out this work. Prepared by .................................................. Tom Sampson BSc MSc FRGS C.WEM MCIWEM Chartered Senior Analyst Maxine Zaidman BSc PhD CEnv MCIWEM C.WEM Technical Director Reviewed by ................................................. Jonathan Cooper BEng MSc DipCD CEng MICE MCIWEM C.WEM MloD Managing Director Purpose This document has been prepared as a Final Report for the EPA. JBA Consulting accepts no responsibility or liability for any use that is made of this document other than by the Client for the purposes for which it was originally commissioned and prepared. JBA Consulting has no liability regarding the use of this report except to the EPA. Copyright © JBA Consulting Engineers and Scientists Ltd 2016 Carbon Footprint A printed copy of the main text in this document will result in a carbon footprint of 363g if 100% post-consumer recycled paper is used and 462g if primary-source paper is used.
    [Show full text]
  • Hydrometry Quality Charter, Guide to Good Practices
    HYDROMETRY QUALITY CHARTER: THE GUIDE TO GOOD PRACTICES INTRODUCTION In this age when IT is king and sophisticated computer modelling is common place, is there still a place for low tech science such as hydrometry ? Is this merely a costly use of manpower and time, yielding only marginal gains in productivity, requiring sophistic justification, of limited interest in a period of increasingly rare money? We've got to take a stand: the overwhelming majority of mathematical models err in their calibration data. Today it is less expensive to create a model than to go out into the field and collect real data. If we scratch beneath the surface of some of these hydrological projects- and certain recent scientific committee opinions remind us of this- we can quickly see the problem and underline the extent to which derived default hypotheses can have consequences not only in terms of risks but also in terms of possible cost overruns. The use of hydrological data is growing rapidly. Beyond the needs for modelling purposes, water use regulations have pushed us to better judge the effect of projects in observing an area and subsequently its fluctuations. Finally, the development of irrigation, using an increasing portion of seasonal discharges, made it necessary to manage this water use, which meant a better real time understanding of discharges. The quality charter, created by the HYDRO database user committee, shows that the hydrometry techniques have greatly evolved over the last fifteen years. There has always been an overriding concern for traceability, so that tomorrow's enlightened critics will be able to obtain current as well as historical data.
    [Show full text]
  • Commission for Hydrology
    Commission for Hydrology Fifteenth session Rome 7–13 December 2016 Abridged final report with resolutions and recommendations WEATHER CLIMATE WATER CLIMATE WEATHER WMO-No. 1184 Commission for Hydrology Fifteenth session Rome 7–13 December 2016 Abridged final report with resolutions and recommendations WEATHER CLIMATE WATER CLIMATE WEATHER WMO-No. 1184 WMO-No. 1184 © World Meteorological Organization, 2016 The right of publication in print, electronic and any other form and in any language is reserved by WMO. Short extracts from WMO publications may be reproduced without authorization, provided that the complete source is clearly indicated. Editorial correspondence and requests to publish, reproduce or translate this publication in part or in whole should be addressed to: Chairperson, Publications Board World Meteorological Organization (WMO) 7 bis, avenue de la Paix Tel.: +41 (0) 22 730 84 03 P.O. Box 2300 Fax: +41 (0) 22 730 81 17 CH-1211 Geneva 2, Switzerland E-mail: [email protected] ISBN 978-92-63-11184-5 NOTE The designations employed in WMO publications and the presentation of material in this publication do not imply the expression of any opinion whatsoever on the part of WMO concerning the legal status of any country, territory, city or area, or of its authorities, or concerning the delimitation of its frontiers or boundaries. The mention of specific companies or products does not imply that they are endorsed or recommended by WMO in preference to others of a similar nature which are not mentioned or advertised. This report contains the text as adopted by Plenary and has been issued without formal editing.
    [Show full text]
  • 1 Introduction
    INTRODUCTION 1 ___________________________________________________________________________ 1 INTRODUCTION 1.1 Definition of Hydrology and Hydrometry Hydrology is a multidisciplinary subject that deals with the occurrence, circulation and distribution of the waters of the Earth. In other words, hydrology is the study of the location and movement of inland water, both frozen and liquid, above and below ground. The domain of hydrology embraces the physical, chemical, and biological reaction of water in natural and manmade environment (Chow et al, 1988). Hydrometry means literally water measurement. In the past hydrometric engineers were particularly involved in streamflow measurements. Today many aspects of water measurements are included.Hydrometry is defined in this course as the measurement of flow in open watercourses, supported or complemented by the measurements of water levels, bed levels and sediment transport.About hydrometry will be indicussed in detail in the last chapter. Hydrology is applied to major water and civil engineering projects such as irrigation schemes, dams and hydroelectric power, and in planning water supply projects. Hydrological information is essential in: (1) Estimating reservoir storage capacity that is needed to ensure adequate water supplies for municipal, irrigation and hydropower needs. (2) Planning water resources projects the peak discharge and its volume of flood that have to be adopted in design of irrigation, hydropower, and flood control projects. If the selected flood is too high, it results in a conservative and unnecessary costly structures while adoption of a low design flood can result in the loss of the structure itself and devastating damage to downstream residence and properties. (3) Estimating the impact of watershed management on the quantity and quality of the surface and the groundwater resources.
    [Show full text]
  • Guide to Hydrological Practices
    World Meteorological Organization GUIDE TO HYDROLOGICAL PRACTICES Fifth edition 1994 DATA ACQUISITION AND PROCESSING, ANALYSIS, FORECASTING AND WMO-No. 168 OTHER APPLICATIONS CONTENTS Page Preface ..................................................................... xxix PART A — GENERAL CHAPTER 1 — INTRODUCTION TO THE GUIDE ...................... 1 1.1 Scope of the Guide ................................................. 1 1.2 Plan and content of the Guide ....................................... 1 1.3 Cross-reference between the Guide and the HOMS Reference Manual ............................................................ 3 CHAPTER 2 — WATER-RELATED ACTIVITIES OF WMO ............ 5 2.1 General overview .................................................. 5 2.1.1 Purpose and scope of water-related activities ........................ 6 2.1.2 Programme organization ........................................... 9 2.1.3 Programme implementation ........................................ 10 2.1.4 Human-resources development ..................................... 11 2.1.5 Technical cooperation .............................................. 11 2.2 International databases ............................................. 11 2.2.1 Hydrological Information Referral Service (INFOHYDRO) ........ 11 2.2.2 Global Runoff Data Centre (GRDC) ................................ 12 2.2.3 World Climate Data Information Referral Service (INFOCLIMA) . 13 2.3 The Hydrological Operational Multipurpose System (HOMS)....... 14 2.3.1 Structure of HOMS ...............................................
    [Show full text]
  • Manual on Hydrometry
    Government of India & Government of The Netherlands DHV CONSULTANTS & DELFT HYDRAULICS with HALCROW, TAHAL, CES, ORG & JPS VOLUME 4 HYDROMETRY FIELD MANUAL - PART I NETWORK DESIGN AND SITE SELECTION Field Manual – Hydrometry (SW) Volume 4 – Part I Table of Contents GENERAL 1 1 STEPS IN THE NETWORK DESIGN PROCESS 1-1 1.1 OVERVIEW OF STEPS 1-1 1.2 MAPS AND BACKGROUND INFORMATION 1-1 1.3 DEFINITION OF PURPOSES AND OBJECTIVES OF NETWORK 1-2 1.4 INITIAL EVALUATION OF THE NETWORK, ADEQUACY OF EXISTING NETWORK AND PRIORITISATION 1-2 1.5 COST OF NETWORK 1-3 1.6 NETWORK IMPLEMENTATION PLAN 1-4 1.7 SITE SELECTION SURVEYS 1-4 2 SITE SELECTION OF WATER LEVEL AND STREAMFLOW STATIONS 2-1 2.1 DEFINITION OF OBJECTIVES 2-1 2.2 SITE SURVEYS 2-1 2.2.1 DESK STUDY 2-1 2.2.2 RECONNAISSANCE SURVEYS 2-2 2.2.3 TOPOGRAPHIC SURVEYS 2-2 2.2.4 OTHER SURVEY WORK 2-2 2.3 SELECTION OF WATER LEVEL GAUGING SITES 2-3 2.4 SELECTION OF STREAMFLOW MEASUREMENT SITE 2-4 2.4.1 GUIDELINES FOR SELECTION OF CURRENT METER GAUGING SITE 2-4 2.4.2 REQUIREMENTS FOR FLOAT MEASUREMENTS FOR DISCHARGE ESTIMATION 2-5 2.4.3 SITE SELECTION REQUIREMENTS FOR USE OF ACOUSTIC DOPPLER CURRENT PROFILER (ADCP) FOR DISCHARGE MONITORING 2-6 2.4.4 REQUIREMENTS FOR USE OF SLOPE-AREA METHOD FOR DISCHARGE ESTIMATION 2-6 2.4.5 SELECTION OF NATURAL CONTROL (RATED SECTION) STATION SITE 2-7 2.4.6 SELECTION OF ARTIFICIAL CONTROL SITES 2-8 2.5 FLOW PARAMETERS AND FORMULAE 2-10 APPENDIX 2.1 CHECK LIST FOR SELECTION OF HYDROLOGICAL OBSERVATION SITES 2-13 Hydrometry January 2003 Page i Field Manual – Hydrometry (SW) Volume 4 – Part I GENERAL The Field Manual on Hydrometry, comprises the procedures to be carried out to ensure proper execution of design of the hydrometric network, and operation and maintenance of water level and streamflow gauging stations.
    [Show full text]
  • Hydrological Data Management: Present State and Trends
    WORLD METEOROLOGICAL ORGANIZATION OPERATIONAL HYDROLOGY REPORT No. 48 HYDROLOGICAL DATA MANAGEMENT: PRESENT STATE AND TRENDS By A. Terakawa WMO-No. 964 Secretariat of the World Meteorological Organization – Geneva – Switzerland THE WORLD METEOROLOGICAL ORGANIZATION The World Meteorological Organization (WMO), of which 187* States and Territories are Members, is a specialized agency of the United Nations. The purposes of the Organization are: (a) To facilitate worldwide cooperation in the establishment of networks of stations for the making of meteorological observations as well as hydrological and other geophysical observations related to meteorology, and to promote the establishment and maintenance of centres charged with the provision of meteorological and related services; (b) To promote the establishment and maintenance of systems for the rapid exchange of meteorological and related infor- mation; (c) To promote standardization of meteorological and related observations and to ensure the uniform publication of observations and statistics; (d) To further the application of meteorology to aviation, shipping, water problems, agriculture and other human activi- ties; (e) To promote activities in operational hydrology and to further close cooperation between Meteorological and Hydrological Services; and (f) To encourage research and training in meteorology and, as appropriate, in related fields and to assist in coordinating the international aspects of such research and training. (Convention of the World Meteorological Organization, Article
    [Show full text]